cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A142100 Duplicate of A093838.

Original entry on oeis.org

37, 73, 109, 181, 397, 433, 541, 577, 613, 757, 829, 937, 1009, 1117, 1153, 1297
Offset: 1

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Author

Keywords

A176549 Primes of the form 2*n^2+6*n+1.

Original entry on oeis.org

37, 109, 541, 757, 1009, 1297, 1621, 2377, 6841, 7561, 8317, 9109, 11701, 12637, 15661, 16741, 19009, 23977, 25309, 28081, 34057, 38917, 40609, 42337, 44101, 47737, 51517, 55441, 57457, 59509, 65881, 70309, 72577, 82009, 84457, 99901
Offset: 1

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Author

Vincenzo Librandi, Apr 20 2010

Keywords

Comments

Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
2*a(n) + 7 is a square. - Vincenzo Librandi, Apr 09 2015

Links

Crossrefs

Primes in A059993.
Subsequence of A093838.
Cf. Primes of the form 2*n^2+2*(2*k+3)*n+(2*k+1): this sequence (k=0), A154577 (k=2), A154592 (k=3), A154601 (k=4), A217494 (k=7), A217495 (k=10), A217496 (k=11), A217497 (k=12), A217498 (k=13), A217499 (k=16), A217500 (k=17), A217501 (k=18), A217620 (k=19), A217621 (k=21).

Programs

  • Magma
    [a: n in [0..300] | IsPrime(a) where a is 2*n^2+6*n+1]; // Vincenzo Librandi, Jul 26 2012
  • Mathematica
    Select[Table[2 n^2 + 6 n + 1, {n, 2000}], PrimeQ] (* Vincenzo Librandi, Jul 26 2012 *)

Extensions

Removed an obviously incorrect part of the definition - R. J. Mathar, Apr 21 2010
Showing 1-2 of 2 results.

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